Page 177 of 314

Front compartment
176
>> Operation
Service flapYou can remove the service flap and hang it on
the front of the vehicle so that it does not get
damaged or dirty.
!
Check the fill levels at regular intervals.
!
Carefully remove ice, snow, and any other
deposits from the air intake grilles above the
service flap to ensure air intake at all times.>Park the vehicle on level ground.
>Turn off the engine.
>Set the parking brake.
1
Lever
2
Service flap
>Removing: Fold both levers
1 outwards in
the direction of the arrows.
Service flap
2 is unlocked.
>Lift service flap2 at the front.
>Remove service flap2.
G
Warning!
Always turn key in starter switch to
position0 and remove the key from the
starter switch before opening the ser
vice flap.
If the windshield wipers should inadvert
ently be switched on, you could be seri
ously injured by the wiper washer drive,
which is located just below the service
flap.
G
Warning!
Make sure that the service flap is locked
while driving. Otherwise, the service flap
could become detached and pose a haz
ard to you or others.G
Warning!
To help prevent personal injury, stay
clear of moving parts when the service
flap is open.
The radiator fan may continue to run for
approximately 30 seconds or may even
restart after the engine has been turned
off. Stay clear of fan blades.
Page 178 of 314
Front compartment
>> Operation
177
1
Opening above front bumper
2
Service flap
> Threading: Thread service flap
2 with the
hooks on the back into both openings
1
above the front bumper.
1
Opening in front of windshield
2
Service flap
> Inserting: Insert service flap
2 into both
openings
1 in front of the windshield.
1
Lever
2
Service flap
>Closing: Close service flap
2.
>Fold both levers
1 inwards in the direction
of the arrows.
Service flap
2 is locked. P88.40263431
P88.40263531
Page 179 of 314

Front compartment
178
>> Operation
Coolant
The engine coolant is a mixture of water and
anticorrosion/antifreeze.
To check the coolant level the vehicle must be
parked on level ground and the engine must
have cooled down. For more information, see
"Coolants" (
page 309).Checking coolant level
The coolant reservoir is located in the front
compartment on the driver’s side.
1
Pressure cap
2
Marking bar
G
Warning!
In order to avoid potentially serious
burns:
• Use extreme caution when opening the
service flap if there are any signs of
steam or coolant leaking from the
cooling system, or if the coolant
temperature warning lampD in the
instrument cluster indicates that the
coolant is overheated.
• Do not remove pressure cap on coolant
reservoir if coolant temperature is
above 158°F (70°C). Allow engine to
cool down before removing cap. The
coolant reservoir contains hot fluid
and is under pressure.
• Using a rag, slowly open the cap ap
proximately
1/2 turn to relieve excess
pressure. If opened immediately,
scalding hot fluid and steam will be
blown out under pressure.
P20.30226531
Page 180 of 314

Front compartment
>> Operation
179
>Allow the radiator to cool down for at least
30 minutes.
>Using a rag, turn pressure cap
1 slowly
approximately one half turn counterclock
wise to release any excess pressure.
>Continue turning pressure cap1
counter
clockwise
and remove it.
The coolant level is correct if the level
• for cold coolant: reaches marking bar
2
visible through the filling opening
• for warm coolant: is approximately 0.6 in
(1.5 cm) higher
>If necessary, add coolant.
Adding coolant
>Add coolant as required. The coolant level
may not exceed the maximum filling level.
>Replace and tighten pressure cap
1.
Windshield/rear window
1 washer
system
Both the windshield and the rear window
1
washer are supplied from the windshield
washer reservoir.
The recommended minimum filling level is
1.06 US qt (1.0 l).
The windshield washer reservoir is located in
the front compartment on the driver’s side.
1
CapDuring all seasons,
• use a windshield washer concentrate la
beled for summer and water for tempera
tures above freezing point.
• use a windshield washer concentrate la
beled for winter and water for tempera
tures below freezing point.
1 coupé only.
P82.35248831
G
Warning!
Windshield washer concentrate is highly
flammable. Fire, naked flames and
smoking are prohibited when windshield
washer concentrate is being handled.
Page 181 of 314

Front compartment
180
>> Operation
!
Always use a windshield washer concen
trate labeled for winter where temperatures
may fall below freezing point. Failure to do so
could result in damage to the washer system/
reservoir.
>Premix the windshield washer fluid in a
suitable container.
Observe mixing ratios depending on the
outside temperature (
page 308).
>Use the tab to pull cap1 upwards.
>Refill the windshield washer reservoir.
>Push cap
1 onto the windshield washer
reservoir.
Brake fluidThe brake fluid level in the brake fluid
reservoir may be too low if the brake warning
lamp in the instrument cluster comes on
(page 34) although the parking brake is
released.
!
If you find that the brake fluid in the brake
fluid reservoir has fallen to the minimum mark
or below, have the brake system checked for
brake pad thickness and leaks immediately.
Contact an authorized smart center immedi
ately. Do not add brake fluid as this will not
solve the problem.
The brake fluid reservoir is located in the
front compartment on the driver’s side.
1
Cap
G
Warning!
During vehicle operation, the boiling
point of the brake fluid is continuously
reduced through the absorption of
moisture from the atmosphere. Under
extremely strenuous operating condi
tions, this moisture content can lead to
the formation of bubbles in the system,
thus reducing the system’s efficiency.
Therefore, the brake fluid must be re
placed regularly. Refer to your vehicle’s
Maintenance Booklet for replacement
interval.P42.00213331
Page 182 of 314
Front compartment
>> Operation
181
Checking brake fluid level
>Perform a visual check of the brake fluid
reservoir.
The brake fluid level is correct when it is
between the minimum mark and the maximum
mark.
• If the brake fluid level has fallen slightly
below the minimum mark, drive to an
authorized smart center.
• If the brake fluid level has fallen
significantly below the minimum mark, call
Roadside Assistance or an authorized
smart center.
Page 183 of 314

Tires and wheels
182
>> Operation Contact an authorized smart center for infor
mation on tested and recommended rims and
tires for summer and winter operation. They
can also offer advice concerning tire service
and purchase.
Modifications to the brake system and wheels
and the use of spacer and brake dust rings
are not permissible.
Important guidelines• Only use sets of tires and rims of the same
type and make.
• Tires must be of the correct size for the
rim.
• Break in new tires for approximately
60 miles (100 km) at moderate speeds.
• Regularly check the tires and rims for
damage. Dented or bent rims can cause tire
inflation pressure loss and damage to the
tire beads.
• If vehicle is heavily loaded, check tire infla
tion pressure and correct as required.
• Do not allow your tires to wear down too far.
Adhesion properties on wet roads are
sharply reduced at tread depths of less
than
1/8in (3 mm).
G
Warning!
Replace rims or tires with the same des
ignation, manufacturer and type as shown
on the original part. Contact an autho
rized smart center for further informa
tion. If incorrectly sized rims and tires
are mounted:
• The wheel brakes or suspension
components can be damaged.
• The operating clearance of the wheels
and the tires may no longer be correct.
G
Warning!
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires
have sustained damage, replace them.
When replacing rims, only use genuine
smart wheel bolts specified for the
particular rim type. Failure to do so can
result in the bolts loosening and possibly
an accident.
Retreaded tires are not tested or recom
mended by smart, since previous damage
cannot always be recognized on retreads.
The operating safety of the vehicle can
not be assured when such tires are used.
Page 184 of 314

Tires and wheels
>> Operation
183 Tire care and maintenance
Regularly check your tire inflation pressure
at least once a month. For more information on
checking tire inflation pressure, see
"Recommended tire inflation pressure"
(page 189)
.
Tire inspection
Every time you check the tire inflation pres
sure, you should also inspect your tires for
the following:
• excessive treadwear (
page 183)
• cord or fabric showing through the tire’s
rubber
• bumps, bulges, cuts, cracks or splits in the
tread or side of the tire
Replace the tire if you find any of the above
conditions.
Life of tire
The service life of a tire is dependent upon
varying factors including but not limited to:
•Driving style
• Tire inflation pressure
•Distance drivenTread depth
Do not allow your tires to wear down too far.
Adhesion properties on wet roads are sharply
reduced at tread depths of less than
1/8in
(3 mm)
.
Treadwear indicators (TWI) are required by
law. These indicators are located in six places
on the tread circumference and become visi
ble at a tread depth of approximately
1/16in
(1.6 mm), at which point the tire is considered
worn and should be replaced.
Recommended minimum tire tread depth:
Summer tires
1/8in (3 mm)
Winter tires
1/6in (4 mm)
G
Warning!
Regularly check the tires for damage.
Damaged tires can cause tire inflation
pressure loss. As a result, you could lose
control of your vehicle.
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires
have sustained damage, replace them.
G
Warning!
Tires should be replaced after 6 years,
regardless of the remaining tread.